The present invention relates to containers including both conduits and vessels lined with glass placed under compression to resist high internal pressure and tensile stresses.
Many vessels and conduits will benefit by the use of a glass lining. For example, if a conduit is to be used in food processing equipment, glass lining is desirable in that it will not retain contaminants and can be easily cleaned. Similarly, materials which are highly contaminant or corrosive and involve environmental problems if released from the container should preferably be stored in glass containers. However, glass conduits and glass vessels are limited in pressures they can support and in stresses they can sustain. Glass is extremely brittle and bending or torsion stresses and high pressure in glass vessels or conduits will lead to an easy fracture of the product. It has been determined that if a glass liner is put into a supporting shell and subjected to compressive forces, the tensile strength of the glass is increased by a factor of three or more and the glass will resist bending, torsion, shock and pressure greater than the uncompressed glass without fracturing. To this end, a material in molten form, preferably one which will expand when it solidifies is inserted into a gap between the glass liner and the outer supporting shell to exert a compressive force on the glass liner. In addition, for lesser pressures, tension and torsion, the filler may merely serve as a supporting force for the glass liner.
It is therefore an object of the present invention to provide glass conduits and vessels in which the glass is placed under a compressive force and will sustain high internal pressures and will be resistant to corrosion from its contents.
It is a further object of the present invention to provide a container for pressurized liquids or gasses with a rigid outer shell and a glass liner, and having means intermediate the shell and liner to place the glass under compression or pre-stress the glass liner so that the liner can withstand high pressures and stresses.
Another object of the present invention is to provide a glass lined container with means intermediate an outer rigid shell and the glass liner to provide a supporting force for the glass liner.
Still a further object of the present invention to provide a glass lined vessel or conduit which can sustain high pressures and high pressure changes without fracture of the vessel or conduit.
These and other objects of the present invention will become apparent from the following description of the present invention.
The present invention comprises a container which may be a closed vessel or conduit for liquid or gaseous material. The container is formed by providing an outer strong and rigid outer shell, preferably a strong metallic shell and a glass liner conforming to the shape of the outer shell but spaced from the inner wall of the outer shell. A molten material which will solidify at or above the normal operation temperature is poured into the spacing between the shell and liner and will expand during solidification to place the glass liner under compression permitting the liner to be used under conditions which would normally break the glass.